blastp is part of the new blast+ package from the NCBI.

blastp searches a protein database using a protein query.

Help on the options available can be found by typing blastp -help

blastp understands the concept of tasks. The following tasks can be requested using the -task option and giving one of the following as the argument:

• blastpTraditional BLASTP to compare a protein query to a protein database.
• blastp-shortBLASTP optimized for queries shorter than 30 residues.